Lai Jiangshan [Sat, 17 Apr 2010 09:00:19 +0000 (17:00 +0800)]
KVM: do not call hardware_disable() on CPU_UP_CANCELED
When CPU_UP_CANCELED, hardware_enable() has not been called at the CPU
which is going up because raw_notifier_call_chain(CPU_ONLINE)
has not been called for this cpu.
Drop the handling for CPU_UP_CANCELED.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Avi Kivity [Mon, 19 Apr 2010 14:25:53 +0000 (17:25 +0300)]
KVM: MMU: Drop cr4.pge from shadow page role
Since commit bf47a760f66ad, we no longer handle ptes with the global bit
set specially, so there is no reason to distinguish between shadow pages
created with cr4.gpe set and clear.
Such tracking is expensive when the guest toggles cr4.pge, so drop it.
KVM: prevent spurious exit to userspace during task switch emulation.
If kvm_task_switch() fails code exits to userspace without specifying
exit reason, so the previous exit reason is reused by userspace. Fix
this by specifying exit reason correctly.
Avi Kivity [Wed, 14 Apr 2010 16:20:03 +0000 (19:20 +0300)]
KVM: MMU: Replace role.glevels with role.cr4_pae
There is no real distinction between glevels=3 and glevels=4; both have
exactly the same format and the code is treated exactly the same way. Drop
role.glevels and replace is with role.cr4_pae (which is meaningful). This
simplifies the code a bit.
As a side effect, it allows sharing shadow page tables between pae and
longmode guest page tables at the same guest page.
Signed-off-by: Avi Kivity <avi@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Jan Kiszka [Wed, 14 Apr 2010 13:50:57 +0000 (15:50 +0200)]
KVM: x86: Terminate early if task_switch_16/32 failed
Stop the switch immediately if task_switch_16/32 returned an error. Only
if that step succeeded, the switch should actually take place and update
any register states.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
KVM: x86: get rid of mmu_only parameter in emulator_write_emulated()
We can call kvm_mmu_pte_write() directly from
emulator_cmpxchg_emulated() instead of passing mmu_only down to
emulator_write_emulated_onepage() and call it there.
Andre Przywara [Sun, 11 Apr 2010 21:07:28 +0000 (23:07 +0200)]
KVM: SVM: implement NEXTRIPsave SVM feature
On SVM we set the instruction length of skipped instructions
to hard-coded, well known values, which could be wrong when (bogus,
but valid) prefixes (REX, segment override) are used.
Newer AMD processors (Fam10h 45nm and better, aka. PhenomII or
AthlonII) have an explicit NEXTRIP field in the VMCB containing the
desired information.
Since it is cheap to do so, we use this field to override the guessed
value on newer processors.
A fix for older CPUs would be rather expensive, as it would require
to fetch and partially decode the instruction. As the problem is not
a security issue and needs special, handcrafted code to trigger
(no compiler will ever generate such code), I omit a fix for older
CPUs.
If someone is interested, I have both a patch for these CPUs as well as
demo code triggering this issue: It segfaults under KVM, but runs
perfectly on native Linux.
Signed-off-by: Andre Przywara <andre.przywara@amd.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Avi Kivity [Sun, 11 Apr 2010 10:05:15 +0000 (13:05 +0300)]
KVM: x86 emulator: Don't overwrite decode cache
Currently if we an instruction spans a page boundary, when we fetch the
second half we overwrite the first half. This prevents us from tracing
the full instruction opcodes.
Fix by appending the second half to the first.
Signed-off-by: Avi Kivity <avi@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Alexander Graf [Wed, 7 Apr 2010 08:03:25 +0000 (10:03 +0200)]
KVM: PPC: Add dequeue for external on BookE
Commit a0abee86af2d1f048dbe99d2bcc4a2cefe685617 introduced unsetting of the
IRQ line from userspace. This added a new core specific callback that I
apparently forgot to add for BookE.
So let's add the callback for BookE as well, making it build again.
Signed-off-by: Alexander Graf <agraf@suse.de> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
This patch does:
- 'sp' parameter in inspect_spte_fn() is not used, so remove it
- fix 'kvm' and 'slots' is not defined in count_rmaps()
- fix a bug in inspect_spte_has_rmap()
Alexander Graf [Wed, 24 Mar 2010 20:48:37 +0000 (21:48 +0100)]
KVM: PPC: Disable MSR_FEx for Cell hosts
Cell can't handle MSR_FE0 and MSR_FE1 too well. It gets dog slow.
So let's just override the guest whenever we see one of the two and mask them
out. See commit ddf5f75a16b3e7460ffee881795aa168dffcd0cf for reference.
Signed-off-by: Alexander Graf <agraf@suse.de> Signed-off-by: Avi Kivity <avi@redhat.com>
Alexander Graf [Wed, 24 Mar 2010 20:48:36 +0000 (21:48 +0100)]
KVM: PPC: Make bools bitfields
Bool defaults to at least byte width. We usually only want to waste a single
bit on this. So let's move all the bool values to bitfields, potentially
saving memory.
Signed-off-by: Alexander Graf <agraf@suse.de> Signed-off-by: Avi Kivity <avi@redhat.com>
Alexander Graf [Wed, 24 Mar 2010 20:48:32 +0000 (21:48 +0100)]
KVM: PPC: Fix dcbz emulation
On most systems we need to emulate dcbz when running 32 bit guests. So
far we've been rather slack, not giving correct DSISR values to the guest.
This patch makes the emulation more accurate, introducing a difference
between "page not mapped" and "write protection fault". While at it, it
also speeds up dcbz emulation by an order of magnitude by using kmap.
Signed-off-by: Alexander Graf <agraf@suse.de> Signed-off-by: Avi Kivity <avi@redhat.com>
Alexander Graf [Wed, 24 Mar 2010 20:48:29 +0000 (21:48 +0100)]
KVM: Add support for enabling capabilities per-vcpu
Some times we don't want all capabilities to be available to all
our vcpus. One example for that is the OSI interface, implemented
in the next patch.
In order to have a generic mechanism in how to enable capabilities
individually, this patch introduces a new ioctl that can be used
for this purpose. That way features we don't want in all guests or
userspace configurations can just not be enabled and we're good.
Signed-off-by: Alexander Graf <agraf@suse.de> Signed-off-by: Avi Kivity <avi@redhat.com>
Alexander Graf [Wed, 24 Mar 2010 20:48:28 +0000 (21:48 +0100)]
KVM: PPC: Implement alignment interrupt
Mac OS X has some applications - namely the Finder - that require alignment
interrupts to work properly. So we need to implement them.
But the spec for 970 and 750 also looks different. While 750 requires the
DSISR and DAR fields to reflect some instruction bits (DSISR) and the fault
address (DAR), the 970 declares this as an optional feature. So we need
to reconstruct DSISR and DAR manually.
Signed-off-by: Alexander Graf <agraf@suse.de> Signed-off-by: Avi Kivity <avi@redhat.com>
Alexander Graf [Wed, 24 Mar 2010 20:48:26 +0000 (21:48 +0100)]
KVM: PPC: Make XER load 32 bit
We have a 32 bit value in the PACA to store XER in. We also do an stw
when storing XER in there. But then we load it with ld, completely
screwing it up on every entry.
Welcome to the Big Endian world.
Signed-off-by: Alexander Graf <agraf@suse.de> Signed-off-by: Avi Kivity <avi@redhat.com>
Alexander Graf [Wed, 24 Mar 2010 20:48:24 +0000 (21:48 +0100)]
KVM: PPC: Implement mfsr emulation
We emulate the mfsrin instruction already, that passes the SR number
in a register value. But we lacked support for mfsr that encoded the
SR number in the opcode.
So let's implement it.
Signed-off-by: Alexander Graf <agraf@suse.de> Signed-off-by: Avi Kivity <avi@redhat.com>
Alexander Graf [Wed, 24 Mar 2010 20:48:22 +0000 (21:48 +0100)]
KVM: PPC: Don't reload FPU with invalid values
When the guest activates the FPU, we load it up. That's fine when
it wasn't activated before on the host, but if it was we end up
reloading FPU values from last time the FPU was deactivated on the
host without writing the proper values back to the vcpu struct.
This patch checks if the FPU is enabled already and if so just doesn't
bother activating it, making FPU operations survive guest context switches.
Signed-off-by: Alexander Graf <agraf@suse.de> Signed-off-by: Avi Kivity <avi@redhat.com>
Alexander Graf [Wed, 24 Mar 2010 20:48:21 +0000 (21:48 +0100)]
KVM: PPC: Split instruction reading out
The current check_ext function reads the instruction and then does
the checking. Let's split the reading out so we can reuse it for
different functions.
Signed-off-by: Alexander Graf <agraf@suse.de> Signed-off-by: Avi Kivity <avi@redhat.com>
Alexander Graf [Wed, 24 Mar 2010 20:48:17 +0000 (21:48 +0100)]
KVM: PPC: Ensure split mode works
On PowerPC we can go into MMU Split Mode. That means that either
data relocation is on but instruction relocation is off or vice
versa.
That mode didn't work properly, as we weren't always flushing
entries when going into a new split mode, potentially mapping
different code or data that we're supposed to.
Signed-off-by: Alexander Graf <agraf@suse.de> Signed-off-by: Avi Kivity <avi@redhat.com>
Avi Kivity [Sun, 14 Mar 2010 08:16:40 +0000 (10:16 +0200)]
KVM: MMU: Disassociate direct maps from guest levels
Direct maps are linear translations for a section of memory, used for
real mode or with large pages. As such, they are independent of the guest
levels.
Teach the mmu about this by making page->role.glevels = 0 for direct maps.
This allows direct maps to be shared among real mode and the various paging
modes.
Gleb Natapov [Sun, 21 Mar 2010 11:08:21 +0000 (13:08 +0200)]
KVM: x86 emulator: add decoding of CMPXCHG8B dst operand
Decode CMPXCHG8B destination operand in decoding stage. Fixes regression
introduced by "If LOCK prefix is used dest arg should be memory" commit.
This commit relies on dst operand be decoded at the beginning of an
instruction emulation.
Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Gleb Natapov [Thu, 18 Mar 2010 13:20:26 +0000 (15:20 +0200)]
KVM: x86 emulator: restart string instruction without going back to a guest.
Currently when string instruction is only partially complete we go back
to a guest mode, guest tries to reexecute instruction and exits again
and at this point emulation continues. Avoid all of this by restarting
instruction without going back to a guest mode, but return to a guest
mode each 1024 iterations to allow interrupt injection. Pending
exception causes immediate guest entry too.
Gleb Natapov [Thu, 18 Mar 2010 13:20:24 +0000 (15:20 +0200)]
KVM: x86 emulator: Move string pio emulation into emulator.c
Currently emulation is done outside of emulator so things like doing
ins/outs to/from mmio are broken it also makes it hard (if not impossible)
to implement single stepping in the future. The implementation in this
patch is not efficient since it exits to userspace for each IO while
previous implementation did 'ins' in batches. Further patch that
implements pio in string read ahead address this problem.
Gleb Natapov [Thu, 18 Mar 2010 13:20:23 +0000 (15:20 +0200)]
KVM: x86 emulator: fix in/out emulation.
in/out emulation is broken now. The breakage is different depending
on where IO device resides. If it is in userspace emulator reports
emulation failure since it incorrectly interprets kvm_emulate_pio()
return value. If IO device is in the kernel emulation of 'in' will do
nothing since kvm_emulate_pio() stores result directly into vcpu
registers, so emulator will overwrite result of emulation during
commit of shadowed register.
Gleb Natapov [Thu, 18 Mar 2010 13:20:21 +0000 (15:20 +0200)]
KVM: x86 emulator: add decoding of X,Y parameters from Intel SDM
Add decoding of X,Y parameters from Intel SDM which are used by string
instruction to specify source and destination. Use this new decoding
to implement movs, cmps, stos, lods in a generic way.
Gleb Natapov [Thu, 18 Mar 2010 13:20:20 +0000 (15:20 +0200)]
KVM: x86 emulator: populate OP_MEM operand during decoding.
All struct operand fields are initialized during decoding for all
operand types except OP_MEM, but there is no reason for that. Move
OP_MEM operand initialization into decoding stage for consistency.
Gleb Natapov [Thu, 18 Mar 2010 13:20:09 +0000 (15:20 +0200)]
KVM: x86 emulator: 0f (20|21|22|23) ignore mod bits.
Resent spec says that for 0f (20|21|22|23) the 2 bits in the mod field
are ignored. Interestingly enough older spec says that 11 is only valid
encoding.
Gleb Natapov [Thu, 18 Mar 2010 13:20:03 +0000 (15:20 +0200)]
KVM: Provide callback to get/set control registers in emulator ops.
Use this callback instead of directly call kvm function. Also rename
realmode_(set|get)_cr to emulator_(set|get)_cr since function has nothing
to do with real mode.
kvm_coalesced_mmio_init() keeps to hold the addresses of a coalesced
mmio ring page and dev even after it has freed them.
Also, if this function fails, though it might be rare, it seems to be
suggesting the system's serious state: so we'd better stop the works
following the kvm_creat_vm().
This patch clears these problems.
We move the coalesced mmio's initialization out of kvm_create_vm().
This seems to be natural because it includes a registration which
can be done only when vm is successfully created.
Avi Kivity [Mon, 15 Mar 2010 11:59:57 +0000 (13:59 +0200)]
KVM: MMU: Reinstate pte prefetch on invlpg
Commit fb341f57 removed the pte prefetch on guest invlpg, citing guest races.
However, the SDM is adamant that prefetch is allowed:
"The processor may create entries in paging-structure caches for
translations required for prefetches and for accesses that are a
result of speculative execution that would never actually occur
in the executed code path."
And, in fact, there was a race in the prefetch code: we picked up the pte
without the mmu lock held, so an older invlpg could install the pte over
a newer invlpg.
Reinstate the prefetch logic, but this time note whether another invlpg has
executed using a counter. If a race occured, do not install the pte.
Signed-off-by: Avi Kivity <avi@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Avi Kivity [Mon, 15 Mar 2010 11:59:56 +0000 (13:59 +0200)]
KVM: MMU: Do not instantiate nontrapping spte on unsync page
The update_pte() path currently uses a nontrapping spte when a nonpresent
(or nonaccessed) gpte is written. This is fine since at present it is only
used on sync pages. However, on an unsync page this will cause an endless
fault loop as the guest is under no obligation to invlpg a gpte that
transitions from nonpresent to present.
Needed for the next patch which reinstates update_pte() on invlpg.
Signed-off-by: Avi Kivity <avi@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Avi Kivity [Mon, 15 Mar 2010 11:59:55 +0000 (13:59 +0200)]
KVM: Don't follow an atomic operation by a non-atomic one
Currently emulated atomic operations are immediately followed by a non-atomic
operation, so that kvm_mmu_pte_write() can be invoked. This updates the mmu
but undoes the whole point of doing things atomically.
Fix by only performing the atomic operation and the mmu update, and avoiding
the non-atomic write.
Signed-off-by: Avi Kivity <avi@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Avi Kivity [Mon, 15 Mar 2010 11:59:54 +0000 (13:59 +0200)]
KVM: Make locked operations truly atomic
Once upon a time, locked operations were emulated while holding the mmu mutex.
Since mmu pages were write protected, it was safe to emulate the writes in
a non-atomic manner, since there could be no other writer, either in the
guest or in the kernel.
These days emulation takes place without holding the mmu spinlock, so the
write could be preempted by an unshadowing event, which exposes the page
to writes by the guest. This may cause corruption of guest page tables.
Fix by using an atomic cmpxchg for these operations.
Signed-off-by: Avi Kivity <avi@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Avi Kivity [Mon, 15 Mar 2010 11:59:53 +0000 (13:59 +0200)]
KVM: MMU: Consolidate two guest pte reads in kvm_mmu_pte_write()
kvm_mmu_pte_write() reads guest ptes in two different occasions, both to
allow a 32-bit pae guest to update a pte with 4-byte writes. Consolidate
these into a single read, which also allows us to consolidate another read
from an invlpg speculating a gpte into the shadow page table.
Signed-off-by: Avi Kivity <avi@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
projects / karo-tx-linux.git / log